1) Krypto the Superdog
The original super-pet. What can be said about Krypto? Far, far too much as virtually every DC continuity has had a different version of the dog. The original debuted in 1955 and, like Beppo, was both Kryptonian and one of Superman’s dad’s test subjects. Alas, his rocket was knocked off course and it arrived on Earth after baby Kal-El had matured into Superboy. (Yes, Supergirl has basically the same origin story.) The original Krypto had all of Superman’s powers and even had a secret identity as the Kent family’s dog Skip—the Kents had to dye a brown spot on his back so people wouldn’t recognize him. In those other continuities, sometimes Krypto has been a regular dog, sometimes he sacrificed himself to save Superman or Superboy, but he’s always a hero. Currently, he’s an escaped experiment by the Project Cadmus organization, a clone of the original Post-Crisis Krypto, a normal dog given to other Cadmus experiment Superboy. But the new Krypto has superpowers. See? I said there was too much to say.
